A. Aubone.

Ecological Modelling, Vol. 175, No. 1, Jun 2004, pp. 55-64.

This study analyses the effect on sustainability of a strategy of exploitation under age-specific survival probabilities fixed through time. Exploitation can be considered an artificial selective mortality that affects the stability of ecological communities. For the exploitation of any single species, it is necessary to obtain some indices that permit to check when the exploitation strategy may become an overexploitation strategy. For fisheries, supposing an asymptotically stable equilibrium exists, the number of recruits per spawning biomass units at the steady state need be bounded, such a boundary being dependent on reproductive parameters. In a previous study, this is shown to be a necessary condition for sustainable exploitation. Also, it was shown that when the stable age structure is 'correctly balanced' then the necessary condition for sustainability is verified. Experience say that in order to maintain the sustainability, it is necessary to have diversity of individuals in the age structure. In this paper, the analysis of how the stable age structure should be, relative to reproduction parameters in order to induce the population collapse is performed. The results show that if the age-specific survival probabilities for ages that contribute to recruitment are too low, then the population tends to extinction. Assuming a stable age structure, there exists an extreme value omega sub(1) super('), for the first component of the stable age structure ( omega sub(1)), related to the age-specific survival probabilities that do not contribute significantly to recruitment. When these survival probabilities are low, omega sub(1) super(') is large and conversely. If omega sub(1)> omega sub(1) super(') then maintaining through time the exploitation strategy, or in other words the age-specific survival probabilities, forces the population to the extinction. This is a sufficient condition for a nonsustainable exploitation strategy. In addition, this result shows that an unbalanced stable age structure as characteristic of nonsustainability. Besides, it is possible to see that the necessary condition for sustainable exploitation is not a sufficient condition. We take the Argentine hake (Merluccius hubbsi) fishery as an example where the necessary condition is true and, nevertheless omega sub(1)> omega sub(1) super('). The analysis allows to reach the conclusion that during the period 1986-1999 this fishery stock was overexploited. The loss of adult specimes and depletion of spawning stock biomass, biomass, and numbers of individuals are characteristic of that time period. Also in this paper, a proposal for an exploitation strategy is analysed, through which recovery and sustainable exploitation for this hake stock are expected. This exploitation strategy contemplates a specific fishing gear and suitable closed areas.

John C. Caldwell.

Population Studies, Vol. 59, No. 1, Mar 2005, pp. 128-131.

John I. Carruthers and Alexander C. Vias.

Journal of Regional Science, Vol. 45, No. 1, February 2005, pp. 21-48

This article adapts a regional adjustment model to examine land use change in the Rocky Mountain West region of the United States. Three interrelated questions motivate the research. How does the proliferation of urban, suburban, and exurban sprawl in the Rocky Mountain West relate to the population and employment growth process? Are population and employment endogenously determined there? And what does this imply for the sustainability of economic development in the region? Through a series of regional adjustment models, the empirical analysis links population and employment growth in the Rocky Mountain West to explicit spatial outcomes and delivers substantive evidence of endogeneity between the two. The results suggest that the longterm prosperity of the region depends on the preservation of the high quality of life it offers, and that greater intergovernmental coordination, careful infrastructure planning, and attention to the character of its economic structure may help to accomplish this. Future research should focus on looking deeper into certain explanatory variables used in this analysis and on developing a better picture of what the spatial equilibrium that regional adjustment models emulate may look like.

Branislav S. Djurdjev.

GeoJournal, Vol. 50, No. 2-3, 2000, pp. 133-138.

The paper considers regional differences in population growth in Serbia and highlights the contrast that has emerged between Kosovo and Metohia and the other regions of the country since World War Two. Due to continuing high fertility coupled with declining mortality, growth in Kosovo and Metohia has been three times greater than in Serbia Proper and five times greater than in Voivodina, regions which have been following closely the European demographic transition. Since the population in Kosovo and Metohia is overwhelmingly Albanian these divergent demographic trends are sharpening ethnic tension as the demographic weight of the Serbs decreases in the country as a whole. At the same time the dominance of the Albanians within the province may well contribute to the independence struggle. Since the maintenance of high fertility, with a relatively slow decline - even in comparison with Albania - could be linked with externalities, it is suggested that a solution might be found in more autonomous development for the province which might bring an increase in local responsibility for sustainable development and a decrease in the currently high level of demographic investment.; Reprinted by permission of Springer

K. Jegasothy.

International Journal of Social Economics, Vol. 26, No. 7/8/9, 1999, pp. 1027-1041.

The link between population proliferation and environmental degradation continues to be a critical issue in many developing countries, denting the development process and leaving unpleasant marks on the socio-economic fabric of the society. These marks are quite distinct to rural and urban regions. Efforts to rectify the situation require regional identification of the problems and the causal socio-economic factors. Based on this a sustainable development approach can be formulated, including environmental protection and decent standards of living. (Original abstract - amended)

Cleophas Lado.

Singapore journal of tropical geography, Vol. 20, No. 2, Dec 1999, pp. 148-168.

This paper examines four issues central to the relationships between environmental resources, population and sustainability in Zimbabwe. First, the conceptualisation of population-resource interrelationships and sustainability. Second, the legal basis of land use practices and origins of land use conflict within and between Zimbabwe's main population groups. Third, the demographic threats to sustainable resource development and the impact of the Structural Adjustment Programmes (SAPs) on rural and urban communities. Fourth, the dynamics of population change and environmental resource use constraints including resettlement and land redistribution or reform programmes. It is concluded that the relationships between environmental degradation and population pressure are complex. Sustainable environmental resource use to supply basic livelihoods can be achieved if appropriate technical expertise or backup is provided to the population. Developing and implementing sustainable resource development strategies in Zimbabwe requires attention to socio-economic and political challenges.; Reprinted by permission of Blackwell Publishers

Brantley Liddle.

Population and Environment, Vol. 21, No. 4, Mar 2000, pp. 385-411.

Explores the development & use of a simulation model that considers sustainability on several levels by calculating production, consumption, investment, population growth/ change, & environmental pollution less environmental quality upgrading investment. This model allows the consideration of population's impact on per capita consumption as well as the social interdependencies among population, per capita consumption, & technology. Under certain population growth scenarios it is found that some countries ultimately consume less pollution, & less pollution is consumed on a system-wide basis. This apparently counterintuitive result is arrived at due to (1) the modeling of the decision to invest in environmental quality upgrading; & (2) the impact of population age structure on investment, not only the impact of total population & population growth on total consumption. 5 Tables, 9 Figures, 30 References. Adapted from the source document.

M. E. Moses and J. H. Brown.

Ecology Letters, Vol. 6, No. 4, Apr 2003, pp. 295-300.

The flux of energy and materials constrains all organisms, and allometric relationships between rates of energy consumption and other biological rates are manifest at many levels of biological organization. Although human ecology is unusual in many respects, human populations also face energetic constraints. Here we present a model relating fertility rates to per capita energy consumption rates in contemporary human nations. Fertility declines as energy consumption increases with a scaling exponent of -1/3 as predicted by allometric theory. The decline may be explained by parental trade-offs between the number of children and the energetic investment in each child. We hypothesize that the -1/3 exponent results from the scaling properties of the networked infrastructure that delivers energy to consumers. This allometric analysis of human fertility offers a framework for understanding the demographic transition to smaller family sizes, with implications for human population growth, resource use and sustainability.

K. L. Ng and J. P. Obbard.

Environment international, Vol. 31, No. 4, May 2005, pp. 483-492.

This review examines the development and application of strategic environmental assessment (SEA) process in the planning framework of Hong Kong. Two strategic planning case studies are evaluated within the context of SEA, namely the Territorial Development Strategy Review (TDS Review) and the Third Comprehensive Transport Study (CTS-3). Rapid population growth and urbanisation in Hong Kong, coupled with a historic lack of planning controls and inherent conflicts between government departments have been major obstacles to achieving sustainable development in the territory. Despite these challenges, Hong Kong was one of the first Asian countries to apply SEA to major development plans, where the implementation of the 'SUSDEV 21' study on sustainable development has demonstrated the government's commitment towards integrated environmental protection. The application of SEA has provided decision-makers with key information on potential environment impacts arising from proposed developments, resulting in greater accountability and transparency in the decision-making process. SEA in Hong Kong has also prompted an increased level of environmental awareness and co-operation between government departments and agencies responsible for the management of Hong Kong's natural and urban environments. However, the application of SEA in Hong Kong continues to have notable limitations. SEA needs to evolve beyond its current sectoral application to examine ways in which development decisions can not only pre-empt and prevent environmental damage, but also positively enhance and restore existing natural resources. Current land use plans and transportation strategies still largely determine the pattern of development in the near future without adequate longer- term environmental cost-benefit analysis. Sustainable development includes environmental, social and economic considerations, and these inter-related elements need be suitably balanced. SEA is not a means to obstruct development in Hong Kong, but should be recognised for its inherent socio-economic and ecological value, and fully integrated with the decision-making process. Whilst it is admirable that Hong Kong has taken positive steps in this direction, it is now an opportune moment for the government to have the foresight and tenacity to create a sustainable development framework for Hong Kong into the future.

Maria-Jose Prados.

Journal of Environmental Planning and Management, Vol. 48, No. 1, January 2005 2005, pp. 65-83.

This paper analyses new dynamics in rural areas of Andalusia belonging to protected environments. These dynamics relate to demographic developments that have taken place over the past 20 years, and their repercussions on changes in the use of land and regional planning in a wider context. The author calls this process "naturbanization", building on the work of Berry and Champion on the concept of counterurbanization. Whilst most of the work on demographic movements and restructuring in rural areas is based on the trends set by city dwellers, this work aims to show the importance of environmental conditions on human behaviour and how this can have medium and long-term repercussions on the population dynamics of rural areas in Andalusia. The main results of this study show clear evidence of a nature urbanization process, as measured by a relative population development, in rural areas where protected natural areas are present. However, there are also clear differences in the population growth rates that support the presence of a naturbanization process between natural parks. In the protected natural areas situated in inland locations, population growth rates have generally been lagging behind while the protected areas situated nearer to the coast have proved to be more attractive to migration and have experienced a positive population development in the 1981-2001 period. Apparently, the presence of protected nature is not the only factor determining the attractiveness of a rural area as a place to live. The naturbanization in rural areas can have negative implications for the ecological, landscape and social values of rural areas and therefore needs careful policy attention.

Irmi Seidl and Clem A. Tisdell.

Ecological Economics, Vol. 31, No. 3, December 1999 1999, pp. 395-408.

In this paper the concept of carrying capacity is investigated to provide an improved understanding about its contribution to solve environmental problems. Light is shed on its form, interpretation and application in biology, demography, applied and human ecology. The analysis begins with an examination of the bedrock of carrying capacity which is Malthus' population theory, and its mathematical formulation--the logistic growth equation. The investigation shows Malthus' thinking to be both political and normative. Furthermore, the rigid assumptions of the logistic equation and the uncertainty of its terms are found not to allow an unequivocal calculation and prediction of the upper limits (carrying capacity) of population growth. It is illustrated that in ecology, carrying capacity focuses on the quality of an ecosystem (pressures on it) and corresponding population numbers, and less on equilibrium of populations as in biology. It is shown that carrying capacity, when applied in fields where human activity or human aims are involved, is a complex normative concept influenced by ecological dynamics, human values and aims, institutional settings and management practices. However, it is demonstrated that the discussion about institutional settings, aims, and values does not take place as much as necessary for its useful application and operationalization in such fields. Instead, authors fall back on sustainability, environmental standards or resilience. The main contribution of carrying capacity in applied and human ecology is as a political concept generally highlighting that exponential growth and thus environmental pressures have to be curbed. Carrying capacity is far from being a universal constraint. Operationalization will continue to be hampered as long as agreements are missing about which social carrying capacity is to be opted for and when it is considered to have been transgressed.

P. Streeten.

Population and Development Review, Vol. 25, No. 2, Jun 1999, pp. 355-360.

This book is published by New York: Oxford University Press, 1998. In the first 6 chapters, Rostow discusses the problems created for employment and social services by a stagnant or falling world population. In the 2 remaining chapters he deals with the role of the USA in the world and the problems of the country's inner cities. Though the water problem will be important in the next century, the importance of the scarcity of time as the ultimately limiting factor goes substantially beyond the production of food. Considers the place of knowledge and the forms of knowledge, and discusses some flaws in Rostow's book. (Original abstract - amended)

D. P. Van Vuuren and L. F. Bouwman.

Ecological Economics, Vol. 52, No. 1, Jan 2005, pp. 43-62.

The Ecological Footprint (EF) has received considerable attention as a useful indicator in the context of sustainable development. So far, it has mostly been applied as a static indicator. Here, we have derived a set of long- term EF scenarios for 17 world regions using the IMAGE 2.2 implementation of the IPCCs SRES scenarios. The scenarios are used to discuss potential trends in EFs in different world regions but also to analyse underlying trends driving changes in the EF. The baseline scenarios show the EF for real land use only (not accounting for CO sub(2)) to increase further in the next few decades in most world regions, being driven by population growth, changes in human diets towards more land-intensive products and overall increases in consumption levels. Future crop yield improvements and technology development will partly offset these trends, resulting in decreasing per capita EFs, but increasing total EFs. In the longer term, EF development may strongly diverge on the basis of assumptions made in the different baseline scenarios (from 5.4 Gha at present to 6.0-8.2 Gha in 2050 depending on the scenario). The aggregated EF following the definition of Wackernagel et al. (Proc. Natl. Acad. Sci. 99 (2002) 9266-9271) (including virtual land for CO sub(2)) increases more strongly, from 12.6 to 20-31 Gha depending on the different scenarios. An alternative scenario was developed to explore whether optimistic assumptions for changes in consumption and production patterns could limit the increase of the global EF, which limited EF increase to 15 Gha in 2050. This scenario still allowed for population growth and strong economic development in low-income regions.

Helen Ware.

Journal of Peace Research, Vol. 42, No. 4, July 2005, pp. 435-454.

This article explores the relationships between demography and internal conflict in the Pacific Island countries, focusing on the three subregions Polynesia, Micronesia and Melanesia. These countries confront distinctive challenges and opportunities because of their unique cultures and non-militarized status, combined with very small size and remote locations. The use of the MIRAB model of island economies based on migration, remittances, aid and bureaucracy is extended to examine its impact on social cohesion and the avoidance of internal conflict. For Polynesia, MIRAB is found to be a sustainable development strategy. Continuous emigration from Polynesia serves to reduce population pressure and communal tensions. Further, remittance income supports the Polynesian economies, and this also reduces the potential for conflict. For Micronesia, except Kiribati and Nauru, migration access to the USA is assured. In contrast, for the Melanesian countries, there is minimal emigration, rapid population growth and considerable intercommunal tension, which has resulted in several coups and one 'failed state'. Demographic pressure created by rapid population growth results in a lack of employment opportunities for youths (who provide the majority of participators in civil unrest and conflicts) rather than in direct pressure on land and other natural resources.

Anthony Young.

Geographical Journal, Vol. 171, No. 1, Mar 2005, pp. 83-95.

Attitudes to population policy taken by major international institutions display a lack of symmetry. Population-based institutions forcefully set out the effects of population on development and human welfare. In contrast, institutions and lobbies concerned with hunger, poverty and environment, brought together at the 2003 World Summit on Sustainable Development in Johannesburg, treat population growth as a given, independent, variable. This paper gives a land resources viewpoint. It includes a case study of Malawi and cross-country statistical comparisons. Official estimates of the extent of spare land, cultivable but not presently cultivated, are challenged. It is concluded that in low-income, food-deficit countries population increase has reduced, in some areas nullified, advances in agricultural development. Following the 1994 UN Conference on Population and Development in Cairo, a set of ethically acceptable measures for reducing population growth received general acceptance. All concerned with poverty, hunger and environment should follow the policy road from Cairo to Johannesburg. If greater efforts are not made to reduce rates of population increase, the targets of the Millennium declaration will not be met, and the suffering which these cause will continue. Statements about agriculture, food security, poverty and sustainability should recognize that population is not an external variable but an integral part of development.; Reprinted by permission of the Royal Geographical Society (with IBG)